Nikolas Hagemann

Ithaka Insitute gGmbH, Germany and Agroscope, Zurich Reckenholz, Switzerland

The growth of biomass is considered the most efficient method currently available to extract carbon dioxide from the atmosphere. However, biomass carbon is easily degraded by microorganisms releasing it in the form of greenhouse gases back to the atmosphere. If biomass is pyrolysed, the organic carbon is converted into solid (biochar), liquid (bio‐...

Implementing advanced wastewater treatment (WWT) to eliminate organic micropollutants (OMPs) is a necessary step to protect vulnerable freshwater ecosystems and water resources. To this end, sorption of OMP by activated carbon (AC) is one viable technology among others. However, conventional AC production based on fossil precursor materials causes...

The use of wood ash as an additive in biochar production was shown to increase biochar yields and was suggested to improve the recycling of ash-derived nutrients. However, there is limited knowledge on the interaction of ash addition with pyrolysis conditions and their effects on biochar yield and properties. Here, we performed experimental pyrolys...

Biochar is obtained by pyrolyzing biomass and is, by definition, applied in a way that avoids its rapid oxidation to CO2. Its use in agriculture includes animal feeding, manure treatment (e.g. as additive for bedding, composting, storage or anaerobic digestion), fertilizer component or direct soil application. Because the feedstock carbon is photos...

Pyrogenic carbon capture and storage (PyCCS), which comprises the production of biomass, its pyrolysis, and the non-oxidative use of the biochar to create carbon sinks, has been identified as a promising negative emission technology with co-benefits by improving soil properties. Using biochar as a soil additive becomes increasingly common as farmer...

Anaerobic digestion and composting of biowastes are vital pathways to recycle carbon and nutrients for agriculture. However, plastic contamination of soil amendments and fertilizers made from biowastes is a relevant source of (micro‐) plastics in (agricultural) ecosystems. To avoid this contamination, plastic containing biowastes could be pyrolyzed...

Chlorinated aromatic hydrocarbons like polychlorinated dibenzo-p-dioxins and -furans (PCDD/F) and polychlorinated biphenyls (PCB) are omnipresent in the environment due to historic production, use, and (unintended) release. Nowadays, their emission and maximum concentration in environmental compartments is strictly regulated. During biochar product...

Fenton-like processes using persulfate for oxidative water treatment and contaminant removal can be enhanced by the addition of redox-active biochar, which accelerates the reduction of Fe(III) to Fe(II) and increases the yield of reactive species that react with organic contaminants. However, available data on the formation of non-radical or radica...

Introduction Soil organic carbon (SOC) content can vary significantly across a given plot. Therefore, a representative sampling is a prerequisite to obtain meaningful results from analysis and of utter importance when SOC quantification is used to quantify (temporary) carbon dioxide removal (CDR). However, certain management practices aiming to inc...

Mechanized biochar field application remains challenging due to biochar’s poor flowability and bulk density. Granulation of biochar with fertilizer provides a product ready for application with well-established machinery. However, it’s unknown whether granulated biochar-based fertilizers (gBBF) are as effective as co-application of non-granulated b...

Activated carbon (AC) has important industrial and environmental applications as it has excellent abilities to sorb contaminants such as per- and polyfluoroalkyl substances (PFAS). Current research aims to develop activated biochars (AB) from renewable biomass to replace AC that is produced from fossil feedstock. Both AC and AB are primarily compri...

The European Biochar Certificate (EBC) guarantees sustainable sourcing of biomass, eco- friendly pyrolysis processes, and a save-to-use biochar. It is a producer and product certification scheme that is prerequisite for participation in most biochar-C-sink certification schemes. In 2023, 64'000 tons of EBC-certified biochar were produced in Europe...

The following text describes how a C-sink certification based on a biochar application is carried out. The procedures are based on the European Biochar Certificate (EBC) C-sink certificate guidelines, version 2.1 of Feb. 01st, 2021. However, they are also exemplary for comparable regulations and certifications and do not claim to be exhaustive. Mos...

Animal manure has been used to manage soil fertility since the dawn of agriculture. It provides plant nutrients and improves soil fertility. In the last decades, animal husbandry has been significantly expanded globally. Its economics were optimized via the (international) trade of feed, resulting in a surplus of animal manure in areas with intensi...

Physical disintegration of biochar has been postulated to determine the persistence and mobility in soil of this recalcitrant carbon pool. Therein, freeze–thaw cycling can induce substantial physical stress to biochars. We here investigated the physical disintegration and subsequent mobilisation of five different biochars under “realistic worst-cas...

Urban stormwater carries dissolved organic and metal contaminants that pose risks to water supplies and the environment. Green infrastructure elements such as biofilters have the potential to capture and treat urban stormwater prior to infiltration to groundwater. Because conventional sand-based biofilters often fail to eliminate dissolved contamin...

Effective and efficient nutrient management is central to best-practice agriculture, facilitat- ing sustainable intensification while reducing negative externalities. The application of biochar-based fertilizers (BBF) in tropical agronomy has the potential to improve nutrient management by enhancing nutrient availability and uptake. Here, we perfor...

The use of biochar is an important tool to improve soil fertility, reduce the negative environmental impacts of agriculture, and build up terrestrial carbon sinks. However, crop yield increases by biochar amendment were not shown consistently for fertile soils under temperate climate. Recent studies show that biochar is more likely to increase crop...

Biochars are considered potential sustainable sorbents to reduce the leaching of per- and polyfluoroalkyl substances (PFAS) from contaminated soils. However, biochar characteristics must probably be optimized to achieve useful sorption capacity. In the present work, eight waste timber biochars were produced, including biochars activated to differen...

Application of biochar has been widely suggested as a remediation tool for trace element-polluted soils, but the impact of biochar on microbial communities and on native plants remain largely unknown. To overcome this knowledge gap, biochar produced from rice husk and olive pit were applied at a rate of 8 t ha−1 into a soil with two contrasting lev...

Land-based greenhouse gas removal (GGR) options include afforestation or reforestation (AR), wetland restoration, soil carbon sequestration (SCS), biochar, terrestrial enhanced weathering (TEW), and bioenergy with carbon capture and storage (BECCS). We assess the opportunities and risks associated with these options through the lens of their potent...

Biochar, that is, carbonized biomass similar to charcoal, has been used in acute medical treatment of animals for many centuries. Since 2010, livestock farmers increasingly use biochar as a regular feed supplement to improve animal health, increase nutrient intake efficiency and thus productivity. As biochar gets enriched with nitrogen-rich organic...

Metal-blending of biomass prior to pyrolysis is investigated in this work as a tool to modify physico-chemical biochar properties and its behavior as adsorbent. Six different compounds were used for metal-blending: AlCl3, Cu(OH)2, FeSO4, KCl, MgCl2 and Mg(OH)2. Pyrolysis experiments were performed at 400 and 700 �C and the characterization of bioch...

As a consequence of Earth's surface oxygenation, ocean geochemistry changed from ferruginous (iron(II)‐rich) into more complex ferro‐euxinic (iron(II)‐sulphide‐rich) conditions during the Paleoproterozoic. This transition must have had profound implications for the Proterozoic microbial community that existed within the ocean water and bottom sedim...

The enrichment culture KS is one of the few existing autotrophic, nitrate-reducing Fe(II)-oxidizing cultures that can be continuously transferred without an organic carbon source. We used a combination of Catalyzed Amplification Reporter Deposition Fluorescence In-Situ Hybridization (CARD-FISH) and Nanoscale Secondary Ion Mass Spectrometry (NanoSIM...

Biochar and activated carbon, both carbonaceous pyrogenic materials, are important products for environmental technology and intensively studied for a multitude of purposes. A strict distinction between these materials is not always possible, and also a generally accepted terminology is lacking. However, research on both materials is increasingly o...

Biochar, a material defined as charred organic matter applied in agriculture, is suggested as a beneficial additive and bulking agent in composting. Biochar addition to the composting feedstock was shown to reduce greenhouse gas emissions and nutrient leaching during the composting process, and to result in a fertilizer and plant growth medium that...

Amending soil with biochar (pyrolized biomass) is suggested as a globally applicable approach to address climate change and soil degradation by carbon sequestration, reducing soil-borne greenhouse-gas emissions and increasing soil nutrient retention. Biochar was shown to promote plant growth, especially when combined with nutrient-rich organic matt...

Recent studies have demonstrated the importance of the nutrient status of biochar and soils prior to its inclusion in particular agricultural systems. Pre-treatment of nutrient-reactive biochar, where nutrients are loaded into pores and onto surfaces, gives improved yield outcomes compared to untreated biochar. In this study we have used a wide sel...

Agriculture and land use change has significantly increased atmospheric emissions of the non-CO2 green-house gases (GHG) nitrous oxide (N2O) and methane (CH4). Since human nutritional and bioenergy needs continue to increase, at a shrinking global land area for production, novel land management strategies are required that reduce the GHG footprint...

Biochars have been recognized as an important material to improve soil properties. In a number of studies their beneficial properties have been found to increase with residence time in soil and during the composting process. The beneficial properties have been correlated with surface functional groups resulting from the interactions between char pa...

Slow release of nitrate by charred organic matter used as a soil amendment (i.e. biochar) was recently suggested as potential mechanism of nutrient delivery to plants which may explain some agronomic benefits of biochar. So far, isolated soil-aged and composted biochar particles were shown to release considerable amounts of nitrate only in extended...

Quantification of mineral N species in the presence of DOC. Introduction and results and discussion of a study on the potential impact of dissolved organic carbon (DOC) on the quantification of nitrate, nitrite and ammonium. (PDF)

Biochar has been shown to improve soil function through increased cation and anion exchange capacity, soil water retention, increased soil buffer capacity, and enhanced microbial growth. Proposed mechanisms by which biochar will increase microbial activity include provision of labile carbon, increased nutrient retention, facilitated electron transf...

The application of biochar as a soil amendment to improve soil fertility has been suggested as a tool to reduce soil-borne CO2 and non-CO2 greenhouse gas emissions, especially nitrous oxide (N2O). Both lab and field trials have demonstrated N2O emission reduction by biochar amendment, but the long-term effect (>1 year) has been questioned. Here we...

Repeated extractions of nitrate and ammonium were performed on compost (Con), biochar-amended composts (CB1, CB2, CB3), soil and biochar-amended soil. Data presents the amount of N released during each step of extraction from each replicate of each treatment.

Today’s food production and consumption go hand in hand with immense damages to humans and nature. Change is needed, but where to start and which direction to go? This article tries to give an interdisciplinary answer by taking recourse to a vision, that is, an ideal image of the future which is drawn upon ethical reflection and beyond the limits o...

Food production is one of the most pressing issues for a sustainable development (SD). Instead of mainstream paths like the utilisation of insect protein, highly efficient soilless hydroponics, aquaculture or precision agriculture, this article focusses on various approaches of organic agriculture. Organic Agriculture is subject to both scientific...

In order to contribute to sustainable development (SD), complex and heterogeneous institutions such as universities need instruments to define SD goals as well as to assess and to communicate their SD performance. We discuss the potential of sustainability indicators to provide structure and guidance for SD processes of universities, analyse the su...

Die Transformation hin zu einer nachhaltigen Entwicklung ist ein wissensba-sierter, ethisch orientierter Suchprozess, zu dem Hochschulen heute in vielfältiger Weise beitragen können. Um diesen Weg besser begehen zu können, ist es notwendig, das Leitbild einer nachhaltigen Entwicklung in konkrete Zielsysteme und Indikatoren zu übertragen. In Deutsch...

Pressing challenges of the 21st century need adequate response of science! This claim is not just a question of working on urgent and relevant questions. This claim calls for new approaches in science. According to the proverb 'The world has problems, universities have faculties' - we have to overcome traditional boundaries of disciplines. Moreover...